1. Technical Field
The subject technology provides solutions for reducing contention in a wireless network, and in particular for reducing wireless contention caused during exchange of Layer 3 and Layer 4 acknowledgement traffic.
2. Introduction
Many wireless local area network (WLAN) deployments are based upon the IEEE 802.11 standards that provide protocols to enable access between mobile devices, and to other networks, such as hard-wired local area and global networks, such as the Internet. In receiving Internet data, a common gateway operating in a conventional IP/TCP protocol may be utilized. The IEEE 802.11 architecture is comprised of several components and services that interact to provide station mobility transparent to higher layers of the network stack. IEEE 802.11 based networks define stations as components that connect to a wireless medium and contain the functionality of the IEEE 802.11 protocols, for example, including MAC (Medium Access Control), PHY (Physical Layer), and connections to the wireless media. Typically, IEEE 802.11 protocols are implemented in the hardware and/or software of a network interface card.
IEEE 802.11 standards also define a Basic Service Set or BSS, which is regarded as a basic building block in WLAN architecture. The BSS consists of a group of access point stations that communicate with one another. In independent BSS, the mobile stations communicate directly with each other. In an infrastructure BSS, all stations in the BSS communicate with the access point and no longer communicate directly with the independent BSS, such that all frames are relayed between stations by the access point.
A station could be a laptop PC, handheld device, or an access point (referred herein as “access point” or “AP”). Stations can be mobile, portable, or stationary, and all stations support the IEEE 802.11 station services of authentication, de-authentication, privacy, and data delivery. The MAC layer's primary function is to provide a fair mechanism to control access of shared wireless media. However, prior to transmitting a frame, the MAC layer must gain access to the network, which it does through two different access mechanisms: a contention-based mechanism, called the distributed coordination function (DCF), and a centrally controlled access mechanism, called the point coordination function (PCF). The PCF modes allow the implementation of a quality of service (QOS) mechanism, but it is optional and requires extra interactions in order to negotiate a QOS between the mobile terminal and the AP. The DCF mode, considered the default mode, does not provide any QOS mechanism. Consequently all stations including the base station AP in WLAN have the same probability to acquire and to send data within the medium. This type of service is referred to as a “best effort.”